1. Field of the Invention
The present invention pertains to mobile telecommunications, and particularly to providing security for mobile telecommunications transmissions.
2. Related Art and other Considerations
In a typical cellular radio system, mobile user equipment units (UEs) communicate via a radio access network (RAN) to one or more core networks. The user equipment units (UEs) can be mobile stations such as mobile telephones (“cellular” telephones) and laptops with mobile termination, and thus can be, for example, portable, pocket, hand-held, computer-included, or car-mounted mobile devices which communicate voice and/or data with radio access network.
The radio access network (RAN) covers a geographical area which is divided into cell areas, with each cell area being served by a base station. A cell is a geographical area where radio coverage is provided by the radio base station equipment at a base station site. Each cell is identified by a unique identity, which is broadcast in the cell. The base stations communicate over the air interface (e.g., radio frequencies) with the user equipment units (UE) within range of the base stations. In the radio access network, several base stations are typically connected (e.g., by landlines or microwave) to a radio network controller (RNC). The radio network controller, also sometimes termed a base station controller (BSC), supervises and coordinates various activities of the plural base stations connected thereto. The radio network controllers are typically connected to one or more core networks.
One example of a radio access network is the Universal Mobile Telecommunications (UMTS) Terrestrial Radio Access Network (UTRAN). The UTRAN is a third generation system which in some respects builds upon the radio access technology known as Global System for Mobile communications (GSM) developed in Europe. UTRAN is essentially a wideband code division multiple access (W-CDMA) system. The Third Generation Partnership Project (3GPP) has undertaken to evolve further the UTRAN and GSM-based radio access network technologies.
In actuality, mobile telecommunications coverage for an area, e.g., a large region or country, may be provided by plural mobile telecommunication operators, each having their own radio access network with the nodes (e.g., network elements) including as those described above, for example. The plural mobile telecommunication operators (e.g., mobile telecommunications companies) must cooperate and communicate with one another to provide for their customers/subscriber services which span networks. For example, subscribers of a first network operated by one operator must be able to place/receive calls with subscribers of a second network maintained by a second operator. Moreover, the subscribers of the first network to be provided with coverage even when in the second network. Such communication and cooperation is effected, at least in part, by signaling between the network operators. Some of this signaling involves usage of the MAP (Mobile Application Part) protocol.
As the migration towards the third generation of mobile networks nears, the security of signaling traffic between the networks of different operators grows in importance. The third generation (3G) network signaling faces a diverse threat situation. The added computational power, the increasing number of operators on the market, and the new technologies available for potential intruders are all factors that contribute to the threat scene that the third generation signaling networks face.
What is needed, therefore, and an object of the present invention, is technique and/or method for securing the signaling traffic between network elements in different operators' networks, thereby preventing illegitimate uses of such information as the MAP (Mobile Application Part) protocol, for example.